Sub Farben()
For i = 1 To ActiveSheet.Rows.Count Step 4
With Rows(i).Interior
.ColorIndex = 4
End With
With Rows(i + 1).Interior
.ColorIndex = 3
End With
With Rows(i + 2).Interior
.ColorIndex = 6
End With
With Rows(i + 3).Interior
.ColorIndex = 5
End With
Next i
End Sub